Célia Sapart

Methane (CH4) and nitrous oxide (N2O) are two strong greenhouse gases. Their atmospheric mixing ratios strongly increased since pre-industrial times largely due to human activities, but the behaviour of their natural sources and sinks are not well understood yet.

The stable isotope (SI) composition of CH4 and N2O of ice core air enables us to better understand the changes in the relative strengths of their sources and sinks in the past. Understanding the past will help to predict their future evolution.

The aim of my research is to reconstruct the past atmospheric history of CH4 and N2O gases at high temporal resolution over the last few millennia.

Moreover, I am investigating the underlying processes leading to CH4 emissions from the polar regions. In order to do so, we analyze CH4 mixing ratios and isotopes in the Arctic Ocean and in the CH4 bubbles trapped in winter permafrost lake ice. This leads to a better understanding on how CH4 is formed in the sediment, and above all, how much is transferred to the atmosphere through the water column.
At a more general level, I am very interested by paleo-research, especially paleaoclimatology, glaciology and paleaoceanography. Understanding the future by looking at the past is simply fascinating!